Vandermonde Matrix

Problem

Build the Vandermonde matrix of the values x with n columns:

V[i][j] = x[i]^j for j = 0, ..., n - 1.

The first column is all ones, and each row is a geometric progression.

Hint

Vandermonde matrices appear when fitting polynomials to data points.

case 1

in: [[1,2,3],3]

expected: [[1,1,1],[1,2,4],[1,3,9]]

case 2

in: [[0,1],2]

expected: [[1,0],[1,1]]

case 3

in: [[2],4]

expected: [[1,2,4,8]]

case 4

in: [[-1,0,1],3]

expected: [[1,-1,1],[1,0,0],[1,1,1]]

Starter codePython

def vandermonde_matrix(x, n):
    # Your code here
    pass

4 test cases · run your code against them in the editor